History of Lyme disease: where it came from and how it was discovered

Quick answer

Lyme disease is far older than its name. Traces of the Lyme bacterium were found in the 5,300-year-old “Iceman,” and doctors in Europe described its rash in 1909. It got its name after a 1975 cluster of arthritis cases in Lyme, Connecticut. In 1982, scientist Willy Burgdorfer identified the bacteria, later named Borrelia burgdorferi after him.

Timeline of Lyme disease

Lyme, Connecticut, 1975: how the disease got its name

In the mid-1970s, many children and adults in the towns around Lyme, Connecticut, developed swollen, painful joints. Several children were told they had juvenile arthritis, which is rare and does not usually cluster in one place. Two local mothers, Polly Murray and Judith Mensch, refused to accept that answer. They contacted the state health department, which connected them with Dr. Allen Steere at Yale.

The state health department and Yale ran a joint survey of the area. Steere and Dr. Stephen Malawista first called the illness “Lyme arthritis.” They noticed many patients had an expanding rash before their joint pain, which pointed toward an insect or tick bite. By 1978 they had shown that deer ticks spread it. The cause was still unknown until Burgdorfer’s discovery in 1982. Patient persistence played a big part in this story, and patient voices remain central today.

Where did Lyme disease come from?

Lyme disease did not start in Connecticut. That is just where it was first recognized in the U.S. as a distinct illness. The evidence points to a very old infection that circulated in wildlife long before anyone named it:

• Ancient DNA. Traces of Lyme bacteria in the Iceman show it infected people in Europe thousands of years ago.
• Early European medicine. European doctors described the migrating rash and linked it to ticks decades before the Connecticut outbreak.
• Old museum samples. Researchers Sam Telford and David Persing tested stored specimens and found the bacteria in Cape Cod mice from 1894 and Long Island ticks from 1945.
• Wide spread. The bacteria are found in the upper Midwest, the Pacific Coast and the South, not just near Long Island. Telford has said genetic data do not support a single point of origin on this continent.

To learn how the bacteria, ticks and wildlife fit together today, see our page about what causes Lyme disease and our guide to ticks that carry Lyme disease.

The Plum Island theory: what is documented and what is not

Plum Island sits off the eastern tip of Long Island, across the water from Lyme, Connecticut. It was home to a federal animal-disease research lab. Because it is so close to where Lyme disease was named, some people have asked whether the disease escaped from there. Journalist Kris Newby’s 2019 book “Bitten” renewed that question. It argues that the U.S. military researched insects and ticks as possible weapons and suggests a possible link to the spread of tickborne diseases. The book is listed in our Lyme disease books guide.

What is documented:

• In July 2019, the U.S. House adopted an amendment, sponsored by Rep. Chris Smith of New Jersey, asking the Defense Department’s inspector general to review whether the department experimented with ticks and insects as biological weapons between 1950 and 1975, and whether any escaped.
• “Bitten” presents interviews and documents its author says show military interest in insect-borne weapons.

What is speculative or contradicted:

• The idea that Lyme disease started at Plum Island conflicts with the evidence above: the bacteria were in Cape Cod mice in 1894 and Long Island ticks in 1945, before the island’s later research activity, and in a European man 5,300 years ago.
• We could not find a published inspector general report confirming that weaponized ticks were released.

Asking questions about government research is reasonable. But the scientific record shows Lyme bacteria were here long before any lab could have released them.

The “Lyme disease breakthrough at Mayo Clinic”

In February 2016, CDC announced that Mayo Clinic researchers had found a new species of Lyme-causing bacteria, Borrelia mayonii. They first noticed unusual lab results from six patients. It appears to be limited to the upper Midwest, mainly Minnesota and Wisconsin, and is spread by the blacklegged tick. Compared with the usual species, it was linked to nausea and vomiting, a more spread-out rash rather than a single bull’s-eye, and higher levels of bacteria in the blood.

How case counting has changed

Numbers matter in Lyme history. In 2022, high-incidence states began reporting cases based on lab results alone, without extra clinical details. Reported cases rose to 62,551, about 68% above the 2017 to 2019 average of 37,118. CDC says this rise mostly reflects the new rules, not a sudden jump in risk. For today’s numbers, see how common Lyme disease is or the state-by-state guide.

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